1 // SPDX-License-Identifier: LGPL-2.1
2 /*
3  *
4  *   Encryption and hashing operations relating to NTLM, NTLMv2.  See MS-NLMP
5  *   for more detailed information
6  *
7  *   Copyright (C) International Business Machines  Corp., 2005,2013
8  *   Author(s): Steve French (sfrench@us.ibm.com)
9  *
10  */
11 
12 #include <linux/fs.h>
13 #include <linux/slab.h>
14 #include "cifspdu.h"
15 #include "cifsglob.h"
16 #include "cifs_debug.h"
17 #include "cifs_unicode.h"
18 #include "cifsproto.h"
19 #include "ntlmssp.h"
20 #include <linux/ctype.h>
21 #include <linux/random.h>
22 #include <linux/highmem.h>
23 #include <linux/fips.h>
24 #include "../smbfs_common/arc4.h"
25 #include <crypto/aead.h>
26 
__cifs_calc_signature(struct smb_rqst * rqst,struct TCP_Server_Info * server,char * signature,struct shash_desc * shash)27 int __cifs_calc_signature(struct smb_rqst *rqst,
28 			struct TCP_Server_Info *server, char *signature,
29 			struct shash_desc *shash)
30 {
31 	int i;
32 	int rc;
33 	struct kvec *iov = rqst->rq_iov;
34 	int n_vec = rqst->rq_nvec;
35 	int is_smb2 = server->vals->header_preamble_size == 0;
36 
37 	/* iov[0] is actual data and not the rfc1002 length for SMB2+ */
38 	if (is_smb2) {
39 		if (iov[0].iov_len <= 4)
40 			return -EIO;
41 		i = 0;
42 	} else {
43 		if (n_vec < 2 || iov[0].iov_len != 4)
44 			return -EIO;
45 		i = 1; /* skip rfc1002 length */
46 	}
47 
48 	for (; i < n_vec; i++) {
49 		if (iov[i].iov_len == 0)
50 			continue;
51 		if (iov[i].iov_base == NULL) {
52 			cifs_dbg(VFS, "null iovec entry\n");
53 			return -EIO;
54 		}
55 
56 		rc = crypto_shash_update(shash,
57 					 iov[i].iov_base, iov[i].iov_len);
58 		if (rc) {
59 			cifs_dbg(VFS, "%s: Could not update with payload\n",
60 				 __func__);
61 			return rc;
62 		}
63 	}
64 
65 	/* now hash over the rq_pages array */
66 	for (i = 0; i < rqst->rq_npages; i++) {
67 		void *kaddr;
68 		unsigned int len, offset;
69 
70 		rqst_page_get_length(rqst, i, &len, &offset);
71 
72 		kaddr = (char *) kmap(rqst->rq_pages[i]) + offset;
73 
74 		rc = crypto_shash_update(shash, kaddr, len);
75 		if (rc) {
76 			cifs_dbg(VFS, "%s: Could not update with payload\n",
77 				 __func__);
78 			kunmap(rqst->rq_pages[i]);
79 			return rc;
80 		}
81 
82 		kunmap(rqst->rq_pages[i]);
83 	}
84 
85 	rc = crypto_shash_final(shash, signature);
86 	if (rc)
87 		cifs_dbg(VFS, "%s: Could not generate hash\n", __func__);
88 
89 	return rc;
90 }
91 
92 /*
93  * Calculate and return the CIFS signature based on the mac key and SMB PDU.
94  * The 16 byte signature must be allocated by the caller. Note we only use the
95  * 1st eight bytes and that the smb header signature field on input contains
96  * the sequence number before this function is called. Also, this function
97  * should be called with the server->srv_mutex held.
98  */
cifs_calc_signature(struct smb_rqst * rqst,struct TCP_Server_Info * server,char * signature)99 static int cifs_calc_signature(struct smb_rqst *rqst,
100 			struct TCP_Server_Info *server, char *signature)
101 {
102 	int rc;
103 
104 	if (!rqst->rq_iov || !signature || !server)
105 		return -EINVAL;
106 
107 	rc = cifs_alloc_hash("md5", &server->secmech.md5,
108 			     &server->secmech.sdescmd5);
109 	if (rc)
110 		return -1;
111 
112 	rc = crypto_shash_init(&server->secmech.sdescmd5->shash);
113 	if (rc) {
114 		cifs_dbg(VFS, "%s: Could not init md5\n", __func__);
115 		return rc;
116 	}
117 
118 	rc = crypto_shash_update(&server->secmech.sdescmd5->shash,
119 		server->session_key.response, server->session_key.len);
120 	if (rc) {
121 		cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
122 		return rc;
123 	}
124 
125 	return __cifs_calc_signature(rqst, server, signature,
126 				     &server->secmech.sdescmd5->shash);
127 }
128 
129 /* must be called with server->srv_mutex held */
cifs_sign_rqst(struct smb_rqst * rqst,struct TCP_Server_Info * server,__u32 * pexpected_response_sequence_number)130 int cifs_sign_rqst(struct smb_rqst *rqst, struct TCP_Server_Info *server,
131 		   __u32 *pexpected_response_sequence_number)
132 {
133 	int rc = 0;
134 	char smb_signature[20];
135 	struct smb_hdr *cifs_pdu = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
136 
137 	if (rqst->rq_iov[0].iov_len != 4 ||
138 	    rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
139 		return -EIO;
140 
141 	if ((cifs_pdu == NULL) || (server == NULL))
142 		return -EINVAL;
143 
144 	spin_lock(&cifs_tcp_ses_lock);
145 	if (!(cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) ||
146 	    server->tcpStatus == CifsNeedNegotiate) {
147 		spin_unlock(&cifs_tcp_ses_lock);
148 		return rc;
149 	}
150 	spin_unlock(&cifs_tcp_ses_lock);
151 
152 	if (!server->session_estab) {
153 		memcpy(cifs_pdu->Signature.SecuritySignature, "BSRSPYL", 8);
154 		return rc;
155 	}
156 
157 	cifs_pdu->Signature.Sequence.SequenceNumber =
158 				cpu_to_le32(server->sequence_number);
159 	cifs_pdu->Signature.Sequence.Reserved = 0;
160 
161 	*pexpected_response_sequence_number = ++server->sequence_number;
162 	++server->sequence_number;
163 
164 	rc = cifs_calc_signature(rqst, server, smb_signature);
165 	if (rc)
166 		memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
167 	else
168 		memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8);
169 
170 	return rc;
171 }
172 
cifs_sign_smbv(struct kvec * iov,int n_vec,struct TCP_Server_Info * server,__u32 * pexpected_response_sequence)173 int cifs_sign_smbv(struct kvec *iov, int n_vec, struct TCP_Server_Info *server,
174 		   __u32 *pexpected_response_sequence)
175 {
176 	struct smb_rqst rqst = { .rq_iov = iov,
177 				 .rq_nvec = n_vec };
178 
179 	return cifs_sign_rqst(&rqst, server, pexpected_response_sequence);
180 }
181 
182 /* must be called with server->srv_mutex held */
cifs_sign_smb(struct smb_hdr * cifs_pdu,struct TCP_Server_Info * server,__u32 * pexpected_response_sequence_number)183 int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server,
184 		  __u32 *pexpected_response_sequence_number)
185 {
186 	struct kvec iov[2];
187 
188 	iov[0].iov_base = cifs_pdu;
189 	iov[0].iov_len = 4;
190 	iov[1].iov_base = (char *)cifs_pdu + 4;
191 	iov[1].iov_len = be32_to_cpu(cifs_pdu->smb_buf_length);
192 
193 	return cifs_sign_smbv(iov, 2, server,
194 			      pexpected_response_sequence_number);
195 }
196 
cifs_verify_signature(struct smb_rqst * rqst,struct TCP_Server_Info * server,__u32 expected_sequence_number)197 int cifs_verify_signature(struct smb_rqst *rqst,
198 			  struct TCP_Server_Info *server,
199 			  __u32 expected_sequence_number)
200 {
201 	unsigned int rc;
202 	char server_response_sig[8];
203 	char what_we_think_sig_should_be[20];
204 	struct smb_hdr *cifs_pdu = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
205 
206 	if (rqst->rq_iov[0].iov_len != 4 ||
207 	    rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
208 		return -EIO;
209 
210 	if (cifs_pdu == NULL || server == NULL)
211 		return -EINVAL;
212 
213 	if (!server->session_estab)
214 		return 0;
215 
216 	if (cifs_pdu->Command == SMB_COM_LOCKING_ANDX) {
217 		struct smb_com_lock_req *pSMB =
218 			(struct smb_com_lock_req *)cifs_pdu;
219 		if (pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE)
220 			return 0;
221 	}
222 
223 	/* BB what if signatures are supposed to be on for session but
224 	   server does not send one? BB */
225 
226 	/* Do not need to verify session setups with signature "BSRSPYL "  */
227 	if (memcmp(cifs_pdu->Signature.SecuritySignature, "BSRSPYL ", 8) == 0)
228 		cifs_dbg(FYI, "dummy signature received for smb command 0x%x\n",
229 			 cifs_pdu->Command);
230 
231 	/* save off the origiginal signature so we can modify the smb and check
232 		its signature against what the server sent */
233 	memcpy(server_response_sig, cifs_pdu->Signature.SecuritySignature, 8);
234 
235 	cifs_pdu->Signature.Sequence.SequenceNumber =
236 					cpu_to_le32(expected_sequence_number);
237 	cifs_pdu->Signature.Sequence.Reserved = 0;
238 
239 	cifs_server_lock(server);
240 	rc = cifs_calc_signature(rqst, server, what_we_think_sig_should_be);
241 	cifs_server_unlock(server);
242 
243 	if (rc)
244 		return rc;
245 
246 /*	cifs_dump_mem("what we think it should be: ",
247 		      what_we_think_sig_should_be, 16); */
248 
249 	if (memcmp(server_response_sig, what_we_think_sig_should_be, 8))
250 		return -EACCES;
251 	else
252 		return 0;
253 
254 }
255 
256 /* Build a proper attribute value/target info pairs blob.
257  * Fill in netbios and dns domain name and workstation name
258  * and client time (total five av pairs and + one end of fields indicator.
259  * Allocate domain name which gets freed when session struct is deallocated.
260  */
261 static int
build_avpair_blob(struct cifs_ses * ses,const struct nls_table * nls_cp)262 build_avpair_blob(struct cifs_ses *ses, const struct nls_table *nls_cp)
263 {
264 	unsigned int dlen;
265 	unsigned int size = 2 * sizeof(struct ntlmssp2_name);
266 	char *defdmname = "WORKGROUP";
267 	unsigned char *blobptr;
268 	struct ntlmssp2_name *attrptr;
269 
270 	if (!ses->domainName) {
271 		ses->domainName = kstrdup(defdmname, GFP_KERNEL);
272 		if (!ses->domainName)
273 			return -ENOMEM;
274 	}
275 
276 	dlen = strlen(ses->domainName);
277 
278 	/*
279 	 * The length of this blob is two times the size of a
280 	 * structure (av pair) which holds name/size
281 	 * ( for NTLMSSP_AV_NB_DOMAIN_NAME followed by NTLMSSP_AV_EOL ) +
282 	 * unicode length of a netbios domain name
283 	 */
284 	ses->auth_key.len = size + 2 * dlen;
285 	ses->auth_key.response = kzalloc(ses->auth_key.len, GFP_KERNEL);
286 	if (!ses->auth_key.response) {
287 		ses->auth_key.len = 0;
288 		return -ENOMEM;
289 	}
290 
291 	blobptr = ses->auth_key.response;
292 	attrptr = (struct ntlmssp2_name *) blobptr;
293 
294 	/*
295 	 * As defined in MS-NTLM 3.3.2, just this av pair field
296 	 * is sufficient as part of the temp
297 	 */
298 	attrptr->type = cpu_to_le16(NTLMSSP_AV_NB_DOMAIN_NAME);
299 	attrptr->length = cpu_to_le16(2 * dlen);
300 	blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
301 	cifs_strtoUTF16((__le16 *)blobptr, ses->domainName, dlen, nls_cp);
302 
303 	return 0;
304 }
305 
306 /* Server has provided av pairs/target info in the type 2 challenge
307  * packet and we have plucked it and stored within smb session.
308  * We parse that blob here to find netbios domain name to be used
309  * as part of ntlmv2 authentication (in Target String), if not already
310  * specified on the command line.
311  * If this function returns without any error but without fetching
312  * domain name, authentication may fail against some server but
313  * may not fail against other (those who are not very particular
314  * about target string i.e. for some, just user name might suffice.
315  */
316 static int
find_domain_name(struct cifs_ses * ses,const struct nls_table * nls_cp)317 find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp)
318 {
319 	unsigned int attrsize;
320 	unsigned int type;
321 	unsigned int onesize = sizeof(struct ntlmssp2_name);
322 	unsigned char *blobptr;
323 	unsigned char *blobend;
324 	struct ntlmssp2_name *attrptr;
325 
326 	if (!ses->auth_key.len || !ses->auth_key.response)
327 		return 0;
328 
329 	blobptr = ses->auth_key.response;
330 	blobend = blobptr + ses->auth_key.len;
331 
332 	while (blobptr + onesize < blobend) {
333 		attrptr = (struct ntlmssp2_name *) blobptr;
334 		type = le16_to_cpu(attrptr->type);
335 		if (type == NTLMSSP_AV_EOL)
336 			break;
337 		blobptr += 2; /* advance attr type */
338 		attrsize = le16_to_cpu(attrptr->length);
339 		blobptr += 2; /* advance attr size */
340 		if (blobptr + attrsize > blobend)
341 			break;
342 		if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
343 			if (!attrsize || attrsize >= CIFS_MAX_DOMAINNAME_LEN)
344 				break;
345 			if (!ses->domainName) {
346 				ses->domainName =
347 					kmalloc(attrsize + 1, GFP_KERNEL);
348 				if (!ses->domainName)
349 						return -ENOMEM;
350 				cifs_from_utf16(ses->domainName,
351 					(__le16 *)blobptr, attrsize, attrsize,
352 					nls_cp, NO_MAP_UNI_RSVD);
353 				break;
354 			}
355 		}
356 		blobptr += attrsize; /* advance attr  value */
357 	}
358 
359 	return 0;
360 }
361 
362 /* Server has provided av pairs/target info in the type 2 challenge
363  * packet and we have plucked it and stored within smb session.
364  * We parse that blob here to find the server given timestamp
365  * as part of ntlmv2 authentication (or local current time as
366  * default in case of failure)
367  */
368 static __le64
find_timestamp(struct cifs_ses * ses)369 find_timestamp(struct cifs_ses *ses)
370 {
371 	unsigned int attrsize;
372 	unsigned int type;
373 	unsigned int onesize = sizeof(struct ntlmssp2_name);
374 	unsigned char *blobptr;
375 	unsigned char *blobend;
376 	struct ntlmssp2_name *attrptr;
377 	struct timespec64 ts;
378 
379 	if (!ses->auth_key.len || !ses->auth_key.response)
380 		return 0;
381 
382 	blobptr = ses->auth_key.response;
383 	blobend = blobptr + ses->auth_key.len;
384 
385 	while (blobptr + onesize < blobend) {
386 		attrptr = (struct ntlmssp2_name *) blobptr;
387 		type = le16_to_cpu(attrptr->type);
388 		if (type == NTLMSSP_AV_EOL)
389 			break;
390 		blobptr += 2; /* advance attr type */
391 		attrsize = le16_to_cpu(attrptr->length);
392 		blobptr += 2; /* advance attr size */
393 		if (blobptr + attrsize > blobend)
394 			break;
395 		if (type == NTLMSSP_AV_TIMESTAMP) {
396 			if (attrsize == sizeof(u64))
397 				return *((__le64 *)blobptr);
398 		}
399 		blobptr += attrsize; /* advance attr value */
400 	}
401 
402 	ktime_get_real_ts64(&ts);
403 	return cpu_to_le64(cifs_UnixTimeToNT(ts));
404 }
405 
calc_ntlmv2_hash(struct cifs_ses * ses,char * ntlmv2_hash,const struct nls_table * nls_cp)406 static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash,
407 			    const struct nls_table *nls_cp)
408 {
409 	int rc = 0;
410 	int len;
411 	char nt_hash[CIFS_NTHASH_SIZE];
412 	__le16 *user;
413 	wchar_t *domain;
414 	wchar_t *server;
415 
416 	if (!ses->server->secmech.sdeschmacmd5) {
417 		cifs_dbg(VFS, "%s: can't generate ntlmv2 hash\n", __func__);
418 		return -1;
419 	}
420 
421 	/* calculate md4 hash of password */
422 	E_md4hash(ses->password, nt_hash, nls_cp);
423 
424 	rc = crypto_shash_setkey(ses->server->secmech.hmacmd5, nt_hash,
425 				CIFS_NTHASH_SIZE);
426 	if (rc) {
427 		cifs_dbg(VFS, "%s: Could not set NT Hash as a key\n", __func__);
428 		return rc;
429 	}
430 
431 	rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
432 	if (rc) {
433 		cifs_dbg(VFS, "%s: Could not init hmacmd5\n", __func__);
434 		return rc;
435 	}
436 
437 	/* convert ses->user_name to unicode */
438 	len = ses->user_name ? strlen(ses->user_name) : 0;
439 	user = kmalloc(2 + (len * 2), GFP_KERNEL);
440 	if (user == NULL) {
441 		rc = -ENOMEM;
442 		return rc;
443 	}
444 
445 	if (len) {
446 		len = cifs_strtoUTF16(user, ses->user_name, len, nls_cp);
447 		UniStrupr(user);
448 	} else {
449 		memset(user, '\0', 2);
450 	}
451 
452 	rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
453 				(char *)user, 2 * len);
454 	kfree(user);
455 	if (rc) {
456 		cifs_dbg(VFS, "%s: Could not update with user\n", __func__);
457 		return rc;
458 	}
459 
460 	/* convert ses->domainName to unicode and uppercase */
461 	if (ses->domainName) {
462 		len = strlen(ses->domainName);
463 
464 		domain = kmalloc(2 + (len * 2), GFP_KERNEL);
465 		if (domain == NULL) {
466 			rc = -ENOMEM;
467 			return rc;
468 		}
469 		len = cifs_strtoUTF16((__le16 *)domain, ses->domainName, len,
470 				      nls_cp);
471 		rc =
472 		crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
473 					(char *)domain, 2 * len);
474 		kfree(domain);
475 		if (rc) {
476 			cifs_dbg(VFS, "%s: Could not update with domain\n",
477 				 __func__);
478 			return rc;
479 		}
480 	} else {
481 		/* We use ses->ip_addr if no domain name available */
482 		len = strlen(ses->ip_addr);
483 
484 		server = kmalloc(2 + (len * 2), GFP_KERNEL);
485 		if (server == NULL) {
486 			rc = -ENOMEM;
487 			return rc;
488 		}
489 		len = cifs_strtoUTF16((__le16 *)server, ses->ip_addr, len,
490 					nls_cp);
491 		rc =
492 		crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
493 					(char *)server, 2 * len);
494 		kfree(server);
495 		if (rc) {
496 			cifs_dbg(VFS, "%s: Could not update with server\n",
497 				 __func__);
498 			return rc;
499 		}
500 	}
501 
502 	rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
503 					ntlmv2_hash);
504 	if (rc)
505 		cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
506 
507 	return rc;
508 }
509 
510 static int
CalcNTLMv2_response(const struct cifs_ses * ses,char * ntlmv2_hash)511 CalcNTLMv2_response(const struct cifs_ses *ses, char *ntlmv2_hash)
512 {
513 	int rc;
514 	struct ntlmv2_resp *ntlmv2 = (struct ntlmv2_resp *)
515 	    (ses->auth_key.response + CIFS_SESS_KEY_SIZE);
516 	unsigned int hash_len;
517 
518 	/* The MD5 hash starts at challenge_key.key */
519 	hash_len = ses->auth_key.len - (CIFS_SESS_KEY_SIZE +
520 		offsetof(struct ntlmv2_resp, challenge.key[0]));
521 
522 	if (!ses->server->secmech.sdeschmacmd5) {
523 		cifs_dbg(VFS, "%s: can't generate ntlmv2 hash\n", __func__);
524 		return -1;
525 	}
526 
527 	rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
528 				 ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
529 	if (rc) {
530 		cifs_dbg(VFS, "%s: Could not set NTLMV2 Hash as a key\n",
531 			 __func__);
532 		return rc;
533 	}
534 
535 	rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
536 	if (rc) {
537 		cifs_dbg(VFS, "%s: Could not init hmacmd5\n", __func__);
538 		return rc;
539 	}
540 
541 	if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED)
542 		memcpy(ntlmv2->challenge.key,
543 		       ses->ntlmssp->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
544 	else
545 		memcpy(ntlmv2->challenge.key,
546 		       ses->server->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
547 	rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
548 				 ntlmv2->challenge.key, hash_len);
549 	if (rc) {
550 		cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
551 		return rc;
552 	}
553 
554 	/* Note that the MD5 digest over writes anon.challenge_key.key */
555 	rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
556 				ntlmv2->ntlmv2_hash);
557 	if (rc)
558 		cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
559 
560 	return rc;
561 }
562 
563 int
setup_ntlmv2_rsp(struct cifs_ses * ses,const struct nls_table * nls_cp)564 setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
565 {
566 	int rc;
567 	int baselen;
568 	unsigned int tilen;
569 	struct ntlmv2_resp *ntlmv2;
570 	char ntlmv2_hash[16];
571 	unsigned char *tiblob = NULL; /* target info blob */
572 	__le64 rsp_timestamp;
573 
574 	if (nls_cp == NULL) {
575 		cifs_dbg(VFS, "%s called with nls_cp==NULL\n", __func__);
576 		return -EINVAL;
577 	}
578 
579 	if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED) {
580 		if (!ses->domainName) {
581 			if (ses->domainAuto) {
582 				rc = find_domain_name(ses, nls_cp);
583 				if (rc) {
584 					cifs_dbg(VFS, "error %d finding domain name\n",
585 						 rc);
586 					goto setup_ntlmv2_rsp_ret;
587 				}
588 			} else {
589 				ses->domainName = kstrdup("", GFP_KERNEL);
590 			}
591 		}
592 	} else {
593 		rc = build_avpair_blob(ses, nls_cp);
594 		if (rc) {
595 			cifs_dbg(VFS, "error %d building av pair blob\n", rc);
596 			goto setup_ntlmv2_rsp_ret;
597 		}
598 	}
599 
600 	/* Must be within 5 minutes of the server (or in range +/-2h
601 	 * in case of Mac OS X), so simply carry over server timestamp
602 	 * (as Windows 7 does)
603 	 */
604 	rsp_timestamp = find_timestamp(ses);
605 
606 	baselen = CIFS_SESS_KEY_SIZE + sizeof(struct ntlmv2_resp);
607 	tilen = ses->auth_key.len;
608 	tiblob = ses->auth_key.response;
609 
610 	ses->auth_key.response = kmalloc(baselen + tilen, GFP_KERNEL);
611 	if (!ses->auth_key.response) {
612 		rc = -ENOMEM;
613 		ses->auth_key.len = 0;
614 		goto setup_ntlmv2_rsp_ret;
615 	}
616 	ses->auth_key.len += baselen;
617 
618 	ntlmv2 = (struct ntlmv2_resp *)
619 			(ses->auth_key.response + CIFS_SESS_KEY_SIZE);
620 	ntlmv2->blob_signature = cpu_to_le32(0x00000101);
621 	ntlmv2->reserved = 0;
622 	ntlmv2->time = rsp_timestamp;
623 
624 	get_random_bytes(&ntlmv2->client_chal, sizeof(ntlmv2->client_chal));
625 	ntlmv2->reserved2 = 0;
626 
627 	memcpy(ses->auth_key.response + baselen, tiblob, tilen);
628 
629 	cifs_server_lock(ses->server);
630 
631 	rc = cifs_alloc_hash("hmac(md5)",
632 			     &ses->server->secmech.hmacmd5,
633 			     &ses->server->secmech.sdeschmacmd5);
634 	if (rc) {
635 		goto unlock;
636 	}
637 
638 	/* calculate ntlmv2_hash */
639 	rc = calc_ntlmv2_hash(ses, ntlmv2_hash, nls_cp);
640 	if (rc) {
641 		cifs_dbg(VFS, "Could not get v2 hash rc %d\n", rc);
642 		goto unlock;
643 	}
644 
645 	/* calculate first part of the client response (CR1) */
646 	rc = CalcNTLMv2_response(ses, ntlmv2_hash);
647 	if (rc) {
648 		cifs_dbg(VFS, "Could not calculate CR1 rc: %d\n", rc);
649 		goto unlock;
650 	}
651 
652 	/* now calculate the session key for NTLMv2 */
653 	rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
654 		ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
655 	if (rc) {
656 		cifs_dbg(VFS, "%s: Could not set NTLMV2 Hash as a key\n",
657 			 __func__);
658 		goto unlock;
659 	}
660 
661 	rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
662 	if (rc) {
663 		cifs_dbg(VFS, "%s: Could not init hmacmd5\n", __func__);
664 		goto unlock;
665 	}
666 
667 	rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
668 		ntlmv2->ntlmv2_hash,
669 		CIFS_HMAC_MD5_HASH_SIZE);
670 	if (rc) {
671 		cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
672 		goto unlock;
673 	}
674 
675 	rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
676 		ses->auth_key.response);
677 	if (rc)
678 		cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
679 
680 unlock:
681 	cifs_server_unlock(ses->server);
682 setup_ntlmv2_rsp_ret:
683 	kfree(tiblob);
684 
685 	return rc;
686 }
687 
688 int
calc_seckey(struct cifs_ses * ses)689 calc_seckey(struct cifs_ses *ses)
690 {
691 	unsigned char sec_key[CIFS_SESS_KEY_SIZE]; /* a nonce */
692 	struct arc4_ctx *ctx_arc4;
693 
694 	if (fips_enabled)
695 		return -ENODEV;
696 
697 	get_random_bytes(sec_key, CIFS_SESS_KEY_SIZE);
698 
699 	ctx_arc4 = kmalloc(sizeof(*ctx_arc4), GFP_KERNEL);
700 	if (!ctx_arc4) {
701 		cifs_dbg(VFS, "Could not allocate arc4 context\n");
702 		return -ENOMEM;
703 	}
704 
705 	cifs_arc4_setkey(ctx_arc4, ses->auth_key.response, CIFS_SESS_KEY_SIZE);
706 	cifs_arc4_crypt(ctx_arc4, ses->ntlmssp->ciphertext, sec_key,
707 			CIFS_CPHTXT_SIZE);
708 
709 	/* make secondary_key/nonce as session key */
710 	memcpy(ses->auth_key.response, sec_key, CIFS_SESS_KEY_SIZE);
711 	/* and make len as that of session key only */
712 	ses->auth_key.len = CIFS_SESS_KEY_SIZE;
713 
714 	memzero_explicit(sec_key, CIFS_SESS_KEY_SIZE);
715 	kfree_sensitive(ctx_arc4);
716 	return 0;
717 }
718 
719 void
cifs_crypto_secmech_release(struct TCP_Server_Info * server)720 cifs_crypto_secmech_release(struct TCP_Server_Info *server)
721 {
722 	if (server->secmech.cmacaes) {
723 		crypto_free_shash(server->secmech.cmacaes);
724 		server->secmech.cmacaes = NULL;
725 	}
726 
727 	if (server->secmech.hmacsha256) {
728 		crypto_free_shash(server->secmech.hmacsha256);
729 		server->secmech.hmacsha256 = NULL;
730 	}
731 
732 	if (server->secmech.md5) {
733 		crypto_free_shash(server->secmech.md5);
734 		server->secmech.md5 = NULL;
735 	}
736 
737 	if (server->secmech.sha512) {
738 		crypto_free_shash(server->secmech.sha512);
739 		server->secmech.sha512 = NULL;
740 	}
741 
742 	if (server->secmech.hmacmd5) {
743 		crypto_free_shash(server->secmech.hmacmd5);
744 		server->secmech.hmacmd5 = NULL;
745 	}
746 
747 	if (server->secmech.ccmaesencrypt) {
748 		crypto_free_aead(server->secmech.ccmaesencrypt);
749 		server->secmech.ccmaesencrypt = NULL;
750 	}
751 
752 	if (server->secmech.ccmaesdecrypt) {
753 		crypto_free_aead(server->secmech.ccmaesdecrypt);
754 		server->secmech.ccmaesdecrypt = NULL;
755 	}
756 
757 	kfree(server->secmech.sdesccmacaes);
758 	server->secmech.sdesccmacaes = NULL;
759 	kfree(server->secmech.sdeschmacsha256);
760 	server->secmech.sdeschmacsha256 = NULL;
761 	kfree(server->secmech.sdeschmacmd5);
762 	server->secmech.sdeschmacmd5 = NULL;
763 	kfree(server->secmech.sdescmd5);
764 	server->secmech.sdescmd5 = NULL;
765 	kfree(server->secmech.sdescsha512);
766 	server->secmech.sdescsha512 = NULL;
767 }
768